Michele De Marco

Tenebrio Molitor Meal in Rainbow Trout (Oncorhynchus Mykiss) Diets: Effects on Animal Performance, Nutrient Digestibility and Chemical Composition of Fillets

This study evaluated the effects of diets containing Tenebrio molitor (TM) larvae meal on growth performances, somatic indexes, nutrient digestibility, dorsal muscle proximate and fatty acid (FA) compositions of rainbow trout. Three hundred sixty fish were randomly divided into three groups with four replicates each. The groups were fed diets differing in TM inclusion: 0% (TM0), 25% (TM25) and 50% (TM50) as fed weight basis. Weight gain was not affected by treatment. Feeding rate was significantly higher in TM0 than TM50. Feed conversion ratio was significantly higher in TM0 than TM25 and TM50, while an opposite trend was observed for protein efficiency ratio and specific growth rate. The survival rate was significantly lower in TM0 than TM25 and TM50. The apparent digestibility of protein was significantly lower in the TM50 group than the other groups, while the apparent digestibility of dry matter, organic matter and lipids was unaffected by treatment. If compared to control, the protein and lipid contents of fillets were respectively increased and decreased following TM inclusion in the diet. The Σn3/Σn6 FA ratio of fish dorsal muscle was linearly (TM0>TM25>TM50) reduced by TM inclusion in the diet. Results suggested that TM could be used during the growing phase in trout farming; however, additional studies on specific feeding strategies and diet formulations are needed to limit its negative effects on the lipid fraction of fillets.

Partial or total replacement of soybean oil by black soldier fly larvae (Hermetia illucens L.) fat in broiler diets: effect on growth performances, feed-choice, blood traits, carcass characteristics and meat quality

Abstract The present research studied for the first time the potential application of the fat derived from the black soldier fly larvae fat (BSLF) in substitution to the soybean oil in the diet for broiler chickens: growth performances, feed-choice, blood traits, carcass characteristics and meat quality were considered in this study. A total of 150 male broiler chicks (Ross 308) at one-day of age were randomly allotted to 3 dietary treatments (5 replicates and 10 birds/pen): a basal control diet (C group), and the same diet in which the soybean oil was replaced by 50% (CH group) or 100% (H group) BSLF. Growth performances, feed-choice test, blood traits and slaughtering performances were not influenced by diets. Independently of BSLF inclusion, broiler chickens breast meat had also similar crude protein and ether extract contents and displayed similar thawing loss. Furthermore, pH, L*, a*, b* colour values, and drip loss were unaffected by dietary treatments both at 0 and 9 days of refrigerated storage. As expected, the fatty acid profile of broiler chickens breast was greatly affected by BSLF inclusion level. With increasing BSLF inclusion rate, the proportion of SFA increased (32.2, 37.8, 43.5% for C, CH and H breast meat, respectively, p < .001) to the detriment of the PUFA fraction (22.7, 23.0, 22.9% for C, CH and H breast meat, respectively, p < .001). On the contrary, MUFA fraction was unaffected. BSLF inclusion guaranteed satisfactory productive performances, carcass traits and overall meat quality, thus suggesting that BSLF could be a promising new feed ingredient for chickens.

Effect of genotype and transport on tonic immobility and heterophil/lymphocyte ratio in two local Italian breeds and Isa Brown hens kept under free-range conditions

This study was undertaken to investigate the effect of transport and genotype on the welfare and fear response of laying hens through a comparison of three breeds reared in free-range conditions: a commercial strain, the Isa Brown (IBh), and two local chicken breeds, the Bionda Piemontese (BPh) and the Bianca di Saluzzo (BSh). After a journey of 67 km (75 min) from the farmhouse of origin to the experimental station, ninety hens, divided according to breed, were free-range reared for two months. Body weight (BW), tonic immobility (TI), red and white blood cells, heterophil to lymphocyte (H/L) ratio and 1-acid glycoprotein (AGP) were assessed at four different sampling times: at the farmhouse of origin (T1), at 1 day (T2), 15 days (T3) and at 2 months (T4) after arrival at the experimental station. No statistical differences were found between the four sampling times for BW, total red and white blood cells or for AGP. An increase in the H/L ratio (P<0.05) was recorded at time T2 for IBh and BSh, compared to BPh (P<0.05). TI was significantly higher (P<0.05) for the local breeds, BPh and BSh, than for the commercial strain IBh. The results of this study suggest that genetic and adaptive differences can affect both, physiological and ethological parameters.

Effects of verbascoside supplemented diets on growth performance, blood traits, meat quality, lipid oxidation and histological features in broiler chickens

A trial has been performed to evaluate the effects of dietary verbascoside (VB) on the growth performance, blood traits, meat quality and histological features of broiler chickens. Seventy-two male broiler chickens (Ross 708) were divided into three experimental groups (8 replicates): a control group (C; basal diet), a low VB group (LVB; basal diet+2.5 mg VB/kg feed) and a high VB group (HVB; basal diet+5.0 mg VB/kg feed). The animals were kept in cages, three birds per cage. The trial lasted 35 days. Growth performance and carcass yield were recorded. Blood samples were collected at day 35 in order to evaluate the blood, serum and plasma parameters. As a result of this study, growth and slaughter performances were not affected by the dietary treatments. The LVB and HVB groups showed significantly lower concentrations of total protein (P=0.000), albumin (P=0.000), α-globulin (P=0.001) and β-globulin (P=0.023) than C group. The heterophil to lymphocyte ratio was higher in HVB group than in LVB and C groups (P=0.005). The thiobarbituric acid reactive substances results indicated lower lipid oxidation in the LVB group than in C group. The most relevant histological feature was the lymphoid depletion observed in the thymus and bursa of Fabricius in LVB and HVB. Other studies are still needed to identify the optimal dosage and exposure time of VB dietary supplementation and to further investigate the effects of VB on lymphoid tissue as well as to establish the VB antioxidant effect on broiler chickens.

An association between feather damaging behavior and corticosterone metabolite excretion in captive African grey parrots (Psittacus erithacus).

Background African grey parrots (Psittacus erithacus) are kept as pets and are frequently hand-reared. It has been observed that hand-reared African grey parrots may develop behavioral disorders such as feather damaging behavior (FDB). It is well known that chronic stress is involved in behavioral disorders in captive parrots. The main glucocorticoid in birds is corticosterone; its quantification provides information about adrenocortical activity and is considered to be a reliable indicator of stress levels in birds. We analyzed the differences in the excretion of corticosterone metabolites (CM) in the droppings of African grey parrots characterized by: 1. different rearing histories (parent rearing vs. hand rearing); and 2. the presence or absence of FDB in hand-reared parrots. Methods A total of 82 African grey parrots that were kept in captivity were considered. According to breeding methods, three groups of birds were defined: 1. The parent-reared (PR) parrots included birds kept in pairs (n = 30 pairs) with a conspecific partner of the opposite sex. All of these birds were healthy and never showed FDB signs; 2. The healthy hand-reared parrots (H-HR) included pet parrots individually kept, that were hand-reared and did not display any sign of FDB (n = 11, 7 males and 4 females); 3. The FDB hand-reared parrot (FDB-HR) included pet parrots individually kept, that were hand-reared and displayed FDB (n = 11, 7 males and 4 females). Droppings were collected in the morning over three alternating days in autumn 2014 and spring 2015. The CM were determined using a multi-species corticosterone enzyme immunoassay kit. Split-plot repeated-measure ANOVA was used to examine any differences using group, season and group × season as the main factors. Results Different quantities of CM in droppings were found for the three groups. The mean CM value was 587 ng/g in the PR parrots, 494 ng/g in the H-HR parrots and 1,744 ng/g in the FDB-HR parrots, irrespective of the season. The excretion of CM in FDB-HR was significantly higher than in PR or H-HR parrots. CM in droppings were not influenced by the season (autumn vs. spring); furthermore, the interaction between group and sampling season was not significant. Limited to the H-HR and FDB-HR groups, a trend in the significance of the difference in the mean CM excreted by male and female birds was observed, with the levels excreted by males being higher than those excreted by females. When the effect of age was considered (in the two separate groups), there was a statistically significant positive correlation only for H-HR. Conclusions The highest amount of CM excretion was found in FDB-HR parrots, and a positive correlation between age and CM excretion was found in H-HR. Given that the CM excretion of both PR and H-HR parrots was similar in our study, future research is recommended to investigate the specific aspects of hand-rearing to improve parrot welfare.

Feather picking in pet parrots: sensitive species, risk factor and ethological evidence

Abstract The goals of this study were to estimate the prevalence of feather picking (FP) in Italian pet parrots and evaluate the risk factors and possible ethological correlation. A web survey was created and addressed to owners of all species of companion parrots, distributed through on line parrots association websites, social networks and by mail. The survey was available for compilation from June to October 2014. In 292 compiled surveys, 20 different parrots genera were indicated; Psittacus spp. (24.3%), Agapornis spp. (19.5%), Nymphicus hollandicus (18.0%) and Amazona spp. (9.0%) were the most represented species. Our study showed a FP prevalence of 17.5%, with the highest prevalence in Agapornis spp. (26.3%) and Psittacus spp. (22.5%). Living with other parrots was positively associated to FP (p < 0.05), such as being fed in neonatal age and weaned by the breeder and not by the final owner (p < 0.001). Moreover, 2.9% of non-FP parrots and 10.0% of FP parrots lived always caged (p = 0.06). A significant difference in the feather picking site was detected (p < 0.001). The most affected body region was the chest (58.8%), followed by the rump (41.2%) and under wing regions (25.4%). At the same time, we conducted another study to better understand some information from the hand-raised parrots through a comparison with the parent-raised parrots. We recorded 1488 parent-raised parrots, and only 1.3% were affected by feather loss. This finding confirm that FP is be considered a multi-factorial behavioral pathology in which factors of different origin may cause behavioral disorders associated to self-injuries.

Effects of abrupt housing changes on the welfare of Piedmontese cows

Abstract The Italian Piedmontese cattle breed is traditionally housed in tie-stalls and, to a lesser extent, in loose housing systems with free stalls. The present study has compared the same group of 15 cattle before and after stable renovation (tie-stall vs free-stall housing) funded by Regulation (EU) No. 1305/2013. All the animals remained healthy during the trial, no clinical signs were observed and no mastitis occurred. The tested parameters were: locomotion scoring system, salivary cortisol, blood parameters, serum acute phase protein (albumin, haptoglobin, serum amyloid A and lysozyme). Samples were collected 3 times: before the change (T1), 3 days later (T2), 40 days later (T3). The change in housing determined noteworthy variations in the stress parameters: albumin and total protein displayed the lowest value at T2, while lysozyme displayed the lowest value at T3. Among the App, SAA and Hp were not affected by the sampling time. Salivary cortisol displayed the highest value at T1. This study suggests that tie-stall housing can endanger the welfare of animals, and it is hoped that this farming system will be abandoned in the future.

Distinguishing industrial meat from that of indigenous chickens with molecular markers

&NA; The aim of investigation was to evaluate a traceability system to detect industrial chicken meat among indigenous products, considering issues that could affect assignment accuracy. The dataset included 2 Italian indigenous meat breeds, namely Bionda Piemontese (2 ecotypes) and Bianca di Saluzzo, one broiler line, and 3 layer lines. Assignment tests were performed using a standard panel of 28 microsatellite loci. To evaluate effects of inbreeding and substructure on assignment accuracy, a simulated dataset was prepared. Broilers and layers belong to homogeneous populations and never enter the clusters of indigenous breeds. Ambiguity or misallocation are expected between the Bionda ecotypes and between the 2 indigenous breeds, but it is unlikely that niche products provided by Bionda and Bianca will compete with one another. Non‐random mating reduces accuracy, but only populations having weak genetic differentiation are involved, namely those that are less interesting to discriminate. The dataset can be used as a reference population to distinguish commercial meat from indigenous meat with great accuracy. Misallocations increase as number of loci decreases, but only within or between the indigenous breeds. A subpanel of the most resolving 14 loci keeps sufficient informative content to provide accuracy and to correctly allocate additional test samples within the reference population. This analytical tool is economically sustainable as a method to detect fraud or mislabeling. Adoption of a monitoring system should increase the value of typical products because the additional burden of molecular analyses would improve commercial grade and perception of quality.